So I think there’s something I’m missing as far as how amplifiers work and I was hoping someone could educate me on this: why is RAAL’s Requisite headphones so hard to drive? I see they provide this giant 100WX2 power requirement, but that’s at 0.2ohms. Given that the standard headphone amplifier gives you its initial power output at 32ohms, some 160 times greatest than the rating for the RAAL. Why is it I can’t extrapolate that something like an SMSL SP400 (12W at 32ohms) could provide up to 1,920 W at 0.2ohms, making them accessible for any amplifier that can put out at least 625mW at 32ohms?
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The short answer is that you don’t get the required current automatically. Headphone amps aren’t (generally) designed to source the high currents required to maintain power at low impedances. To put it another way, what an amp can do at 32 ohms doesn’t tell you anything meaningful about what it can do at 0.2 ohms.
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I’m curious to know what your source is and if you’re using a DAC? I have a powerful headphone amp but I wasn’t using it’s full potential until I paired it with a DAC.
You can not just scale 12 W @ 32 Ω down to 0.2 Ω because the amp hits its current limit long before that; power ratings assume the amp *can* supply the required current, which it simply can not into such a tiny load. RAALs are essentially mini speakers with extremely low impedance and sensitivity, so they need a speaker amp (plus RAAL’s interface box) that’s designed to deliver huge current safely into that load.
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Amplifiers are limited by their power supplies and the ratings of the components on the inside, there will be a maximum current and a maximum voltage the supply can provide, neither is infinite.
Driving the Raal requires a ton of current, if you put a 0.2 Ohm load onthe output of most normal amplifiers it would simply draw too much current and either blow a fuse, or some other component on the board would act as a fuse most more complex SS amplifiers will have protection circuits and will treat the RAAL like a short on the output and fault into protention mode.
The transformer solutions like the TI-1A convert volatage into current and viceversa, so you can use a 1/2 W into 32 Ohm amp to drive them with the transformer, because to the amp the load then looks like a 32 Ohm headphone.
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